> ## Documentation Index
> Fetch the complete documentation index at: https://docs.onosso.app/llms.txt
> Use this file to discover all available pages before exploring further.

# Undo a pet change

> Undoes `factId`, the pet's current fact: a removal brings the pet back, a change restores what it replaced, and the pet's first fact takes it out (`current` is `null`). Nothing is deleted.



## OpenAPI

````yaml /openapi.json delete /v1/settings/pets/{petId}/changes/{factId}
openapi: 3.0.0
info:
  title: onosso
  version: 0.0.0
  description: >-
    The household's API: the week, the people and the sessions the web app reads
    and changes.
servers: []
security: []
tags:
  - name: Week
    description: The household's week, day by day.
  - name: People
    description: The people who make up the household.
  - name: Pets
    description: The pets of the house.
  - name: Invites
    description: Links that let someone join.
  - name: Sessions
    description: Where you are signed in.
  - name: Tokens
    description: Your personal API tokens.
  - name: Address
    description: Where the household lives.
  - name: Messages
    description: What each person receives from the product, and when.
  - name: Questions
    description: 'What needs a person: one queue, the same in the app and on WhatsApp.'
  - name: Shopping
    description: 'The household''s one list: places, items and marks.'
  - name: Conversation
    description: >-
      Each person's one conversation with the assistant, the same in the app and
      on WhatsApp.
  - name: MCP
    description: The house for an MCP client such as Claude Desktop, with a personal token.
paths:
  /v1/settings/pets/{petId}/changes/{factId}:
    delete:
      tags:
        - Pets
      summary: Undo a pet change
      description: >-
        Undoes `factId`, the pet's current fact: a removal brings the pet back,
        a change restores what it replaced, and the pet's first fact takes it
        out (`current` is `null`). Nothing is deleted.
      parameters:
        - schema:
            type: string
            maxLength: 64
          required: true
          name: petId
          in: path
        - schema:
            type: string
            maxLength: 64
          required: true
          name: factId
          in: path
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                operationId:
                  type: string
                  format: uuid
                at:
                  type: string
                  format: date-time
              required:
                - operationId
                - at
      responses:
        '200':
          description: The change was undone.
          content:
            application/json:
              schema:
                type: object
                properties:
                  current:
                    allOf:
                      - $ref: '#/components/schemas/Pet'
                      - nullable: true
                required:
                  - current
        '401':
          description: Unauthorized.
        '403':
          description: The request origin is not allowed, or the caller is not a titular.
        '404':
          description: '`household.pet-not-found`: the pet is not in this house.'
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DomainError'
        '409':
          description: '`household.stale-pet`: the pet''s current fact changed.'
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DomainError'
        '422':
          description: '`household.invalid-pet`: a malformed field.'
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/DomainError'
        '503':
          $ref: '#/components/responses/ServiceUnavailable'
        '504':
          $ref: '#/components/responses/RequestTimeout'
      security:
        - session: []
components:
  schemas:
    Pet:
      type: object
      properties:
        id:
          type: string
          description: 'A member of the house: it can be an activity''s subject.'
        factId:
          type: string
          description: >-
            The pet's current fact: the next change's `supersedes`, and what an
            undo names.
        name:
          type: string
        species:
          type: string
          enum:
            - dog
            - cat
            - other
          description: '`dog` (Cachorro), `cat` (Gato) or `other` (Outro).'
        routine:
          type: string
          nullable: true
        source:
          type: string
          enum:
            - settings
        confidence:
          type: string
        appliedAt:
          type: string
          format: date-time
      required:
        - id
        - factId
        - name
        - species
        - routine
        - source
        - confidence
        - appliedAt
    DomainError:
      type: object
      properties:
        code:
          type: string
        details:
          type: object
          additionalProperties:
            nullable: true
      required:
        - code
        - details
    Degraded:
      type: object
      properties:
        code:
          type: string
          enum:
            - request.timeout
            - service.unavailable
        correlationId:
          type: string
      required:
        - code
        - correlationId
  responses:
    ServiceUnavailable:
      description: A dependency is unavailable; retry after Retry-After seconds.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Degraded'
    RequestTimeout:
      description: The request outlived its deadline.
      content:
        application/json:
          schema:
            $ref: '#/components/schemas/Degraded'
  securitySchemes:
    session:
      type: apiKey
      in: cookie
      name: __Secure-better-auth.session_token
      description: The session cookie set when you sign in to the web app.

````

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